CVE-2026-47135 vm2: Sandbox escape via unblocked cross-realm Symbol.for keys + missing bridge write-trap symbol checks
Attackers can escape the vm2 sandbox to execute arbitrary code on the host by exploiting unblocked cross-realm symbols.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-47135?
CVE-2026-47135 is a high-severity code injection vulnerability in patriksimek vm2, published on 12 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
vm2 is an open source vm/sandbox for Node.js. Prior to version 3.11.4, Symbol.for override in setup-sandbox.js only intercepts 2 of 9 dangerous Node.js cross-realm symbols. Combined with the bridge's set/defineProperty/deleteProperty traps having no isDangerousCrossRealmSymbol key check, sandbox code can obtain real cross-realm symbols, write them to host objects, and control host-side behavior — verified with a full util.promisify hijack chain. This issue has been patched in version 3.11.4.
Weakness: CWE-693
Which versions are affected by CVE-2026-47135?
2 open source packages ship an affected version, including vm2.
| Package | Affected | Fixed in |
|---|---|---|
vm2 npm | All versions | 3.11.4 |
vm2 npm | All versions | 3.11.4 |
How do I fix CVE-2026-47135?
Upgrade vm2 to 3.11.4 or later.
Upgrade, and never evaluate templates, expressions or code built from user input. More about Code injection.
Is CVE-2026-47135 being exploited?
There is no known exploitation of CVE-2026-47135 in the wild and no public exploit code.
Sources
Also known as ECHO-3377-7de8-77cf, GHSA-m5q2-4fm3-vfqp, MINI-9q29-2736-7qp5, ROOT-APP-NPM-CVE-2026-47135.